I've worked on a few MGF's and think they're fine tbh. Yes head gaskets go, but they look alright, they go alright, they look good with the roof up & handle ok. It's not badly built either. Yes it uses Metro sub frames but it does the job who cares?
Personally i'd avoid the MX5 more than the MG they rust bad, cambelt is awkward, door handles are a shit idea.
306 cabbies are shite aswell, the roof leaks everywhere, the hydraulics on the roof is a very bad design, and expensive when it goes wrong, heater matrixs are a common fault & theres loads of chassis flex.
& if you consider the Saab 900 then don't thats awful aswell.